Using Boost.Pool requires to link with Boost.System

[Ivan A. Melnikov <iv@…>]

Boost.Pool documentation says:

The Boost Pool library is a header-only library. That means there is no .lib, .dll, or .so to build; just add the Boost directory to your compiler's include file path, and you should be good to go!

But in fact, in boost 1.51.0 on my system (ALT Linux x86_64) it uses Boost.Thread parts which bring Boost.System in, and thus I get the following linking error:

$ cat a.cpp

#include <boost/pool/pool_alloc.hpp>

int main() { return 0; }

$ g++ a.cpp
/tmp/.private/iv/ccqf3pLa.o: In function `__static_initialization_and_destruction_0(int, int)':
a.cpp:(.text+0x4a): undefined reference to `boost::system::generic_category()'
a.cpp:(.text+0x56): undefined reference to `boost::system::generic_category()'
a.cpp:(.text+0x62): undefined reference to `boost::system::system_category()'
collect2: ld returned 1 exit status

Of course, adding -lboost_system helps.

Not shure if it is Boost.Pool, Boost.Thread or just Boost.Pool documentation bug.

[Kohei Takahashi <flast@…>]

This bug caused by r76543.

New dependencies tree:

pool/detail/mutex.hpp
-> thread/mutex.hpp
   -> thread/(pthread|win32)/mutex.hpp
      -> thread/exceptions.hpp
         -> system/error_code.hpp

[Ivan A. Melnikov <iv@…>]

As far as I know, Boost.Thread never promised to be header-only or have header-only parts. Thus, using mutex from Boost.Thread and claiming to be header-only seems to me... erm... a bit unfair, even if it used to work somehow.

I think the best solution would be to switch to using <boost/detail/lightweight_mutex.hpp>, as it is header only and does not have any extra dependencies.

[bimargulies@…]

Is there any way around this to disable the use of the mutex?

[manuel.freiberger@…]

Replying to bimargulies@…:

Is there any way around this to disable the use of the mutex?

I also stumbled across this bug. The pool library pulls the header <boost/thread/mutex.hpp> even if the user has defined BOOST_NO_MT or BOOST_POOL_NO_MT.

It would be good to change line 13 of <boost/thread/mutex.hpp> from #ifdef BOOST_HAS_THREADS to #if defined(BOOST_HAS_THREADS) && !defined(BOOST_NO_MT) && !defined(BOOST_POOL_NO_MT) (this is the complement of the expression from line 32).

This would allow to use Boost.Pool without depending on Boost.System.

[Marshall Clow]

This is a duplicate of #7085